1 .Field of the Invention
The invention relates to an adhesive composition and a medical device comprising an adhesive composition.
2 .Description of the Related Art
Medical devices, such as wound care devices and ostomy appliances may comprise adhesives for direct contact with the skin. It is important that the adhesive is skin-friendly, as the skin often is damaged or just extremely fragile, especially when handling chronic wounds. Different suitable adhesives are known in the art. Hydrocolloid adhesives are often used, due to their permeability and good absorption properties. Acrylic adhesives may also be used, especially for thin applications, as the permeability is low.
Silicone adhesives are very skin-friendly and very suitable for donating active agents, such as in medicated patches, but they are also rather occlusive and hydrophobic, which is a major disadvantage for a product being worn for prolonged period, such as wound dressings, ostomy appliances or incontinence devices.
Attempts have been made for preparing a more hydrophilic silicone adhesive. However, these adhesives tend to be difficult to remove due to a higher tack and lower cohesion, and are thus not very useful for application to fragile or damaged skin.
Another drawback connected to the use of silicone adhesives is the poor absorption properties. This problem may be solved by incorporating absorbent material e.g. in the form of super absorbent particles.
International patent application No. WO 02/087642 discloses an adhesive comprising a hydrophilic phase and a hydrophobic phase. The hydrophobic phase may be a silicone elastomer and the hydrophilic phase may be a water absorbing mixture of hydrophilic polymers of non-silicone origin.
In International patent application No. WO 02/076519 is disclosed a silicone-based moisture absorbing matrix for wound care products. The sticky matrix comprises silicone, gelling agent and optionally a silicone resin. Both silicone compounds are hydrophobic and the reference is silent with respect to the use of hydrophilic silicone.